7 ms·

Someone is jamming BBC broadcasts in the Middle East

135 points by finnw 14y ago

citricsquid 14y ago
Does anyone have any information on how this could be done? Does this require high tech broadcasting equipment to intercept the transmissions (government sponsored?) or is it something that anyone could do?
- trotsky 14y ago
  anyone can do it, for some values of "anyone" that includes having a good power source, some rf equipment and a few books. mostly the problem involves defending the equipment when people unhappy about said behavior arrive.
  - brador 14y ago
    How would you track or locate such a jamming device? is it possible?
    - marklabedz 14y ago
      Very possible. In fact, some aircraft and ship navigation systems (prior to GPS) at a very basic level determine position through triangulation based on direction to known RF emitters. (See Loran, NDB, etc). Its also a popular sub-activity of HAM radio, in which its called "Foxhunting."
    - trotsky 14y ago
      I can't say for sure how "they" do it, but there are a number of options available. Radio in general is very leaky - even rather low power and directional beams can be detected off axis if they travel enough distance and you have sensitive enough equipment. In general you just need a few antennas (or even one, if your're a masochist) and an ability to point them at things. Check for when the signal is the strongest, and check for timing between the receivers and you can get a very good idea of where the transmission comes from. In practice you could do this with multiple antennas (an array) on a single satellite, multiple other satellites or spacecraft, or simply an aircraft or trucks if you control the ground space. I'm willing to bet it's usually done on the targeted bird itself, they aren't completely cut off from communication, have multiple antennas and can even adjust their attitude if it was necessary. This is broadly how the SETI program works for example.
    - xradionut 14y ago
      Yes, location is possible, narrow directional signal makes it more difficult to locate than omnidirectional broadcast signal.
    - ars 14y ago
      It's extremely easy to locate the jamming device! The device is transmitting at high power, it's like beacon, and very easy to see. If you do it in war the jamming station is likely to be visited by a http://en.wikipedia.org/wiki/Anti-radiation_missile http://en.wikipedia.org/wiki/Anti-radiation_missile such as the http://en.wikipedia.org/wiki/HARM_missile http://en.wikipedia.org/wiki/HARM_missile
    - jff 14y ago
      If you'd like a good demonstration of how a jamming device could be found, simply buy a high-power 10 meter radio transciever and set it up to constantly transmit music at 28.400 MHz. You'll effectively monopolize the frequency over a large distance, and within a very short period of time the FCC will arrive to demonstrate their RF tracking techniques. And to levy a huge fine. Do not do this.
      - dsl 14y ago
        The FCC won't care, but a bunch of angry HAMs will be riding their rascal scooters around your neighborhood with directional antennas. Calling channels are defined by the ARRL, not the FCC.
        jff 14y ago
        The FCC will care if you are transmitting without a license, broadcasting (rather than performing 2-way communications), and sending music--all three of these are violations of FCC regulations. Once they determine that it's an ongoing disruption, they will come out with a direction-finding rig, as they have in the past for "pirate" operators causing disruption. Oh, and HAM is not an acronym, it's just ham.
    - JabavuAdams 14y ago
      Think of it this way: radio is light. There's a light sensor on a satellite that the BBC shines at. Someone else is shining a really-bright light at the satellite so it can't "see" the BBC's light through the glare of the other bright light. Kind of like trying to see a flashlight when someone's shining headlights at you. But ... if you're shining a really bright light then everyone who cares to look can see where it's coming from.
trotsky 14y ago
In unrelated news, the EU forced persian TV channels off these transponders a few days ago, citing the "targeted" sanctions intended to prevent Iran from drifting further afield.
- kps 14y ago
  The word ‘persian’ there is a little misleading. The European satellite providers stopped carrying the Iranian government's channels, not Persian-language channels in general.
  - fleitz 14y ago
    Apparently the BBC opposes the removal of the iranian/persian channels as well. From the article "we strongly condemn any practice designed to disrupt audiences’ free access to news and information."
    - tankenmate 14y ago
      It maybe true that the BBC opposes this, but at the same time the BBC is beholden to UK and EU law; i.e. follow the law or be fined and/or loose all your licenses.
thepumpkin1979 14y ago
Since I'm not a native English speaker, I had to google what "Jamming" was about and found this article in Wikipedia where actually explains the difference between Jamming and Interference. http://en.wikipedia.org/wiki/Radio_jamming http://en.wikipedia.org/wiki/Radio_jamming
jgrahamc 14y ago
This isn't that hard to do. You just need a dish, a suitable power source and point it at the satellite. Because of the, in general, wide area that a satellite is looking down on the transmitter can be anywhere in quite a wide area (even when you are talking about the relatively narrow uplink antenna). Given that these satellites are geostationary they can be seen from a very wide area on the ground. Back in 2003 Telstar-12 was jammed from a station in Cuba apparently run by Iran (http://www.atimes.com/atimes/Middle_East/EH22Ak03.html http://www.atimes.com/atimes/Middle_East/EH22Ak03.html) to block transmissions to the Americas and Europe.
- ovi256 14y ago
  You seem to describe satellite uplink jamming: perturbing the link going from the content provider to the satellite. I would expect this uplink would be redundant and encrypted in some way. Maybe even using optical communication for it, which would enable having a very narrow uplink receiver. Thinking about it, jamming the downlink in a large area to get the same effect seems to be much harder than jamming the uplink.
  - davidcuddeback 14y ago
    Encryption doesn't counter jamming, because jamming happens at the physical layer (RF).
    - mturmon 14y ago
      In this case, I'm sure you're right. But it might be worth noting that you can use spread-spectrum techniques (http://en.wikipedia.org/wiki/Spread_spectrum http://en.wikipedia.org/wiki/Spread_spectrum) to overcome jamming. Spread spectrum has some similarities to an encryption scheme, because the method used to smear the signal around uses a pseudorandom sequence which is known to the encoder and the decoder. CDMA (http://en.wikipedia.org/wiki/Code_division_multiple_access http://en.wikipedia.org/wiki/Code_division_multiple_access) cell phones use this idea. As you note, this type of encryption takes place at the RF level.
denzil_correa 14y ago
Isn't the title a bit misleading? I think Europe should be included as well.
- adaml_623 14y ago
  That's really curious I don't know why anyone would write just Middle East rather than Europe and the Middle East. Finnw care to comment?
coin 14y ago
This is not as bad as when NATO bombed Libya's TV station during its attack on Gaddafi.
kadjar 14y ago
Looks like it's coming from Syria: http://www.google.com/hostednews/afp/article/ALeqM5hXpzxDWlSkzvnoluujHCSgaus50w?docId=CNG.b7490d699f872ba1c830ddc9ac429b95.d21 http://www.google.com/hostednews/afp/article/ALeqM5hXpzxDWlS...
- aes256 14y ago
  That link is dead for me, but here's an article from The Telegraph with the same allegation citing "sources within broadcasting companies". Apparently Syria sought Iranian assistance to disrupt the signals. http://www.telegraph.co.uk/news/worldnews/middleeast/syria/9618937/Syria-accused-of-blocking-BBC-broadcasts.html http://www.telegraph.co.uk/news/worldnews/middleeast/syria/9...
bitcartel 14y ago
"We strongly condemn any practice designed to disrupt audiences’ free access to news and information." The identity of the culprit should be obvious! http://www.tvlicensing.co.uk/ http://www.tvlicensing.co.uk/
zupreme 14y ago
I have to wonder why the BBC would release this. What is the motivation? Obviously whoever is "jamming" them is not going to read this, say, "My bad" and just stop. I am really wondering who their real audience, in this case, is. Is this an attempt to influence government actions in the U.K. or the EU itself? Is this part of a public opinion swaying operation to sway the British people so that more of them will support the idea of military action in Syria? It's all speculation at this point, but I do wonder.
- marshray 14y ago
  If you were a global international media company and someone were jamming your signal over a region of the planet wouldn't you put out a short, factual press release too? If nothing else, it will help some of the affected viewers know to quit smacking their televisions on the side.
- njharman 14y ago
  News is news.
balancdreviews 14y ago
Shortwave radio to the rescue.
taybin 14y ago
Or something...!

135 points by finnw 14y ago

Does anyone have any information on how this could be done? Does this require high tech broadcasting equipment to intercept the transmissions (government sponsored?) or is it something that anyone could do?

trotsky 14y ago
anyone can do it, for some values of "anyone" that includes having a good power source, some rf equipment and a few books. mostly the problem involves defending the equipment when people unhappy about said behavior arrive.
- brador 14y ago
  How would you track or locate such a jamming device? is it possible?
  - marklabedz 14y ago
    Very possible. In fact, some aircraft and ship navigation systems (prior to GPS) at a very basic level determine position through triangulation based on direction to known RF emitters. (See Loran, NDB, etc). Its also a popular sub-activity of HAM radio, in which its called "Foxhunting."
  - trotsky 14y ago
    I can't say for sure how "they" do it, but there are a number of options available. Radio in general is very leaky - even rather low power and directional beams can be detected off axis if they travel enough distance and you have sensitive enough equipment. In general you just need a few antennas (or even one, if your're a masochist) and an ability to point them at things. Check for when the signal is the strongest, and check for timing between the receivers and you can get a very good idea of where the transmission comes from. In practice you could do this with multiple antennas (an array) on a single satellite, multiple other satellites or spacecraft, or simply an aircraft or trucks if you control the ground space. I'm willing to bet it's usually done on the targeted bird itself, they aren't completely cut off from communication, have multiple antennas and can even adjust their attitude if it was necessary. This is broadly how the SETI program works for example.
  - xradionut 14y ago
    Yes, location is possible, narrow directional signal makes it more difficult to locate than omnidirectional broadcast signal.
  - ars 14y ago
    It's extremely easy to locate the jamming device! The device is transmitting at high power, it's like beacon, and very easy to see. If you do it in war the jamming station is likely to be visited by a http://en.wikipedia.org/wiki/Anti-radiation_missile http://en.wikipedia.org/wiki/Anti-radiation_missile such as the http://en.wikipedia.org/wiki/HARM_missile http://en.wikipedia.org/wiki/HARM_missile
  - jff 14y ago
    If you'd like a good demonstration of how a jamming device could be found, simply buy a high-power 10 meter radio transciever and set it up to constantly transmit music at 28.400 MHz. You'll effectively monopolize the frequency over a large distance, and within a very short period of time the FCC will arrive to demonstrate their RF tracking techniques. And to levy a huge fine. Do not do this.
    - dsl 14y ago
      The FCC won't care, but a bunch of angry HAMs will be riding their rascal scooters around your neighborhood with directional antennas. Calling channels are defined by the ARRL, not the FCC.
      - jff 14y ago
        The FCC will care if you are transmitting without a license, broadcasting (rather than performing 2-way communications), and sending music--all three of these are violations of FCC regulations. Once they determine that it's an ongoing disruption, they will come out with a direction-finding rig, as they have in the past for "pirate" operators causing disruption. Oh, and HAM is not an acronym, it's just ham.
  - JabavuAdams 14y ago
    Think of it this way: radio is light. There's a light sensor on a satellite that the BBC shines at. Someone else is shining a really-bright light at the satellite so it can't "see" the BBC's light through the glare of the other bright light. Kind of like trying to see a flashlight when someone's shining headlights at you. But ... if you're shining a really bright light then everyone who cares to look can see where it's coming from.

trotsky 14y ago

In unrelated news, the EU forced persian TV channels off these transponders a few days ago, citing the "targeted" sanctions intended to prevent Iran from drifting further afield.

kps 14y ago
The word ‘persian’ there is a little misleading. The European satellite providers stopped carrying the Iranian government's channels, not Persian-language channels in general.
- fleitz 14y ago
  Apparently the BBC opposes the removal of the iranian/persian channels as well. From the article "we strongly condemn any practice designed to disrupt audiences’ free access to news and information."
  - tankenmate 14y ago
    It maybe true that the BBC opposes this, but at the same time the BBC is beholden to UK and EU law; i.e. follow the law or be fined and/or loose all your licenses.

thepumpkin1979 14y ago

Since I'm not a native English speaker, I had to google what "Jamming" was about and found this article in Wikipedia where actually explains the difference between Jamming and Interference. http://en.wikipedia.org/wiki/Radio_jamming http://en.wikipedia.org/wiki/Radio_jamming

jgrahamc 14y ago

This isn't that hard to do. You just need a dish, a suitable power source and point it at the satellite. Because of the, in general, wide area that a satellite is looking down on the transmitter can be anywhere in quite a wide area (even when you are talking about the relatively narrow uplink antenna). Given that these satellites are geostationary they can be seen from a very wide area on the ground. Back in 2003 Telstar-12 was jammed from a station in Cuba apparently run by Iran (http://www.atimes.com/atimes/Middle_East/EH22Ak03.html http://www.atimes.com/atimes/Middle_East/EH22Ak03.html) to block transmissions to the Americas and Europe.

ovi256 14y ago
You seem to describe satellite uplink jamming: perturbing the link going from the content provider to the satellite. I would expect this uplink would be redundant and encrypted in some way. Maybe even using optical communication for it, which would enable having a very narrow uplink receiver. Thinking about it, jamming the downlink in a large area to get the same effect seems to be much harder than jamming the uplink.
- davidcuddeback 14y ago
  Encryption doesn't counter jamming, because jamming happens at the physical layer (RF).
  - mturmon 14y ago
    In this case, I'm sure you're right. But it might be worth noting that you can use spread-spectrum techniques (http://en.wikipedia.org/wiki/Spread_spectrum http://en.wikipedia.org/wiki/Spread_spectrum) to overcome jamming. Spread spectrum has some similarities to an encryption scheme, because the method used to smear the signal around uses a pseudorandom sequence which is known to the encoder and the decoder. CDMA (http://en.wikipedia.org/wiki/Code_division_multiple_access http://en.wikipedia.org/wiki/Code_division_multiple_access) cell phones use this idea. As you note, this type of encryption takes place at the RF level.

denzil_correa 14y ago

Isn't the title a bit misleading? I think Europe should be included as well.

adaml_623 14y ago
That's really curious I don't know why anyone would write just Middle East rather than Europe and the Middle East. Finnw care to comment?

coin 14y ago

This is not as bad as when NATO bombed Libya's TV station during its attack on Gaddafi.

kadjar 14y ago

Looks like it's coming from Syria: http://www.google.com/hostednews/afp/article/ALeqM5hXpzxDWlSkzvnoluujHCSgaus50w?docId=CNG.b7490d699f872ba1c830ddc9ac429b95.d21 http://www.google.com/hostednews/afp/article/ALeqM5hXpzxDWlS...

aes256 14y ago
That link is dead for me, but here's an article from The Telegraph with the same allegation citing "sources within broadcasting companies". Apparently Syria sought Iranian assistance to disrupt the signals. http://www.telegraph.co.uk/news/worldnews/middleeast/syria/9618937/Syria-accused-of-blocking-BBC-broadcasts.html http://www.telegraph.co.uk/news/worldnews/middleeast/syria/9...

bitcartel 14y ago

"We strongly condemn any practice designed to disrupt audiences’ free access to news and information." The identity of the culprit should be obvious! http://www.tvlicensing.co.uk/ http://www.tvlicensing.co.uk/

zupreme 14y ago

I have to wonder why the BBC would release this. What is the motivation? Obviously whoever is "jamming" them is not going to read this, say, "My bad" and just stop. I am really wondering who their real audience, in this case, is. Is this an attempt to influence government actions in the U.K. or the EU itself? Is this part of a public opinion swaying operation to sway the British people so that more of them will support the idea of military action in Syria? It's all speculation at this point, but I do wonder.

marshray 14y ago
If you were a global international media company and someone were jamming your signal over a region of the planet wouldn't you put out a short, factual press release too? If nothing else, it will help some of the affected viewers know to quit smacking their televisions on the side.
njharman 14y ago
News is news.

balancdreviews 14y ago

Shortwave radio to the rescue.

taybin 14y ago

Or something...!